Although the present invention can be applied to any composite fiber components, said present invention and the problem on which it is based are explained in more detail below with reference to planar, stringer-reinforced carbon fiber plastic (CFK) components, for example skin panels of an aircraft.
It is generally known to reinforce carbon fiber plastic skin panels with carbon fiber plastic stringers in order to withstand the high loads in the field of aircraft together with the lowest possible additional weight. In this context, essentially two types of stringers are distinguished: T and Ω stringers.
The cross section of T stringers is composed of a base and a web. The base forms the connecting surface to the skin panel. The use of skin panels which are reinforced with T stringers is widespread in aircraft construction.
Ω stringers have an approximately hat-shaped profile, with the ends of said profile being connected to the skin panel. In the cured state of Ω stringers they can either be adhesively bonded onto the panel which is also cured or they can be cured at the same time as the panel wet on wet. The latter is desirable because it is more favourable in terms of processing technology. However, in order to carry out wet on wet manufacture of skin panels which are reinforced with Ω stringers, supporting cores or molding cores are necessary in order to secure the dimensionally unstable fiber semi-finished products in the desired Ω shape and support them during the manufacturing process. Skin panels with Ω stringers have, compared to T stringers, the advantage of a better infiltration capability during an infusion method in order to introduce a matrix, for example an epoxy resin, into the fiber semi-finished products. Compared to other known methods for manufacturing composite fiber components such as, for example, the prepreg method, infusion methods can be cost-effective because they permit the use of more cost-effective fiber semi-finished products.
When manufacturing Ω stringers, there is the problem, however, that the material which is used at present for the supporting core or molding core is costly and can be difficult to remove after the Ω stringers have been constructed so that the material which remains in the stringers disadvantageously increases the overall weight of the aircraft.